Potential exploration of Fe3O4/biochar from sludge as the media of bioretention system and its comparison with conventional media.

The selection and configuration of soil media are a core issue of the bioretention system. A porous carbon material of Fe3O4/biochar (BSF) was prepared by adding pickling wastewater to modified sludge biochar, which could serve as a good adsorption performance and cheap media for bioretention system. Through the analytic hierarchy process (AHP), different media were evaluated according to their characteristics. By comparing the characteristics of BSF to bio-ceramic (BC), zeolite (ZE), and activated carbon (AC), it was found that BSF has a larger specific surface area and pore volume. The hydrological characteristics of the medium were also tested. The results show that BSF has better water-absorbing quality and hydraulic conductivity than the other three media, but the water-retention property of the medium seems to be inferior. BSF has stable adsorption performance for ammonia nitrogen (NH4+-N) and total phosphorus (TP) in rainwater. Its high adsorption capacity is maintained at 5-35°C, but it is very susceptible to pH factors. The adsorption process by BSF and other media conforms to pseudo-second-order kinetics and the Langmuir model in rainwater. In general, the performance of BSF is shown to be superior to BC, ZE, and AC, making it a potential medium for bioretention system.

Highly Sensitive and Selective Determination of Tertiary Butylhydroquinone in Edible Oils by Competitive Reaction Induced "On-Off-On" Fluorescent Switch.

As one of most common synthetic phenolic antioxidants, tertiary butylhydroquinone (TBHQ) has received increasing attention due to the potential risk for liver damage and carcinogenesis. Herein, a simple and rapid fluorescent switchable methodology was developed for highly selective and sensitive determination of TBHQ by utilizing the competitive interaction between the photoinduced electron transfer (PET) effect of carbon dots (CDs)/Fe(III) ions and the complexation reaction of TBHQ/Fe(III) ions. This novel fluorescent switchable sensing platform allows determining TBHQ in a wider range from 0.5 to 80 µg mL(-1) with a low detection limit of 0.01 µg mL(-1). Furthermore, high specificity and good accuracy with recoveries ranging from 94.29 to 105.82% in spiked edible oil samples are obtained with the present method, confirming its applicability for the trace detection of TBHQ in a complex food matrix. Thus, the present method provides a novel and effective fluorescent approach for rapid and specific screening of TBHQ in common products, which is beneficial for monitoring and reducing the risk of TBHQ overuse during food storage.

The inhibitory effect of selenium nanoparticles on protein glycation in vitro.

Selenium nanoparticles (Se NPs) possess well-known excellent biological activities and low toxicity, and have been employed for numerous applications except as inhibitors to protein glycation. Herein, the present study is carried out to investigate the inhibitory effect of Se NPs on protein glycation in a bovine serum albumin (BSA)/glucose system. By measuring the amount of glucose covalently bound onto BSA, the formation of fructosamine and fluorescent products, it is found that Se NPs can hinder the development of protein glycation in a dose-dependent but time-independent manner under the selected reaction conditions (55 °C, 40 h). And after comparing the increase of inhibitory rate in different stages, it is observed that Se NPs show the greatest inhibitory effect in the early stage, then in the advanced stage, but no effect in the intermediate stage. Fourier transform infrared spectroscopy characterization of Se NPs collected after glycation and determination of ·OH influence and glyoxal formation show that the mechanism for the inhibitory efficacy of Se NPs is related to their strong competitive activity against available amino groups in proteins, their great scavenging activity on reactive oxygen species and their inhibitory effect on α-dicarbonyl compounds' formation. In addition, it is proved that Se NPs protect proteins from structural modifications in the system and they do not exhibit significant cytotoxicity towards BV-2 and BRL-3A cells at low concentrations (10 and 50 µg mL(-1)). Consequently, Se NPs may be suitable for further in vivo studies as novel anti-glycation agents.